This invention concerns the technical sector of blister pack manufacturing, with particular reference to the operating stages which are implemented, and the means which are employed, to insert articles such as pills, tablets, capsules and the like into a heat-formed blister strip.
In this sector the publication US 2007/0084141 is known, which discloses a type of apparatus for inserting small-sized articles into the cells of a blister strip.
This apparatus operates between a complex consisting of a hopper for loading the articles and an associated dosing channel, and a blister strip which is to be filled with articles, and comprises: a plurality of fill trays, each of which affords housings or seatings superiorly, the number and spatial arrangement of which reproduce a predetermined longitudinal tract of the blister strip; conveyor organs, which convey the fill trays along a ring-wound trajectory which is arranged on two levels, an upper level and a lower level, between a station for filling the seatings of the trays with the articles, and a station for transferring the articles which are loaded in the trays into the corresponding empty cells of a corresponding tract of strip; filling organs, which are provided in the filling station, for filling the seatings of each tray which transits in the station, which filling organs comprise means which cause the fill trays to vibrate and rotating brushes, arranged with an axis thereof transversal to the direction of advancement of the trays, for distributing the articles which are released by the dosing channel into the seatings of the advancing trays; and transfer organs, provided in the transfer station, comprising a sucker tray for transferring the articles which are contained in the seatings of each fill tray into the empty cells of a corresponding longitudinal tract of blister strip.
The blister strip is situated alongside the filling station and at the same height as the upper level thereof, thus enabling the trajectory of the sucker tray between the filling station and the blister strip to be minimized.
Once the fill tray has been emptied of the relative articles, it is lowered to the lower level and positioned at the initial part of the upper branch of an underlying conveyor which transfers the tray towards the terminal part of the conveyor, where suitable means raise the empty tray to the upper level.
The described apparatus is obviously complex, since it is provided with a series of fill trays which must be moved by means of suitable organs along a ring-wound trajectory, and with means which fill the housings of the trays with relative articles.
Blister strip format changeover, that is, the operation for varying the reciprocal arrangement of the cells provided in the strip, requires substitution of all the fill trays, with the attendant costs that this entails regarding both the time necessary to perform the substitution, and the need to stock series of fill trays, each series thereof corresponding to a format of the blister strip; format changeover for the blister strip also entails substitution of the sucker tray.